I see that AZ has found this thread just like I just did. AZ you asked some questions on another thread about this subject and I replied with my limited experience. This appears to be the place to be. As I indicated in that thread I was aware of the issue with super cooling and with the belief that fish were also unable to absorb oxygen if they were stuck in water that was too cold. That is what an expert told me. Whatever the case is I have been successful with HBG, LMB, and crappie in my 1/2 acre pond with bottom air stone diffuser (deepest part of pond) that runs as much as possible in winter to keep the DO level up but not so much as to drive the water temperature too cold. It appears putting the aerator in the deepest area might be a mistake but its worked so far. My rationale was to avoid stratification and give the fish more area to live in. I keep thinking that one of these days something I've done wrong will catch up to me and I'll lose everything but I can't bring myself to change something that's been working. I can't afford a DO meter so I calculated the size of pump and number of stones required to result in a DO much higher than my calculated BOD.
